Families of the victims accompanied black and white hearses in limousines as fire marshals and sheriff's deputies shepherded hundreds more - some in funeral attire, others in everyday clothes - to the service in Floresville, Texas, about 12 miles from the First Baptist Church of Sutherland Springs, where the shooting occurred.
Church member John Holcombe, among the massacre's few survivors, invited the public to attend the funeral of his pregnant wife, Crystal, 36, and three of her children, Greg, 13, Emily, 11, and Megan, nine; his parents, 60-year-old Bryan and Karla Holcombe, 58; a brother, 36-year-old Marc Holcombe, and Marc's 18-month-old daughter, Noah.
They will be buried privately on an unspecified date.
News reporters were barred from entering the event centre and were being held in a pen with two trucks obscuring the view inside.
The gunman, Devin Patrick Kelley, began firing into the church as John Holcombe's father Bryan an assistant pastor, ascended to the pulpit.
Walking up and down the centre aisle, Kelley killed 25 people at the church, including crying babies at point-blank range, according to witness accounts.
Authorities have put the official toll at 26, because Crystal Holcombe was pregnant.
Mr Holcombe was managing the church's audio-visual operations at the back of the building and escaped with minor injuries.
Crystal Holcombe's seven-year-old daughter Evelyn also escaped the barrage of gunfire. Her eldest child, 14-year-old Phillip, had stayed home from church services that day.
Kelley died of what appeared to be a self-inflicted gunshot wound after he fled in a vehicle.
Authorities say Kelley was involved in a domestic dispute with his mother-in-law, a member of the church who was not present that day.
However, among the victims was Lula White, his wife's 71-year-old grandmother.
Kelley had a history of domestic violence: He was given a bad conduct discharge from the Air Force after pleading guilty to assaulting his first wife and stepson.
Under federal law, anyone convicted of domestic violence cannot purchase a firearm. But the Air Force failed to inform federal law enforcement authorities that Kelley had been court-martialed.
When he tried to buy guns after his release from a military prison, his conviction was not in the database used to conduct background checks, and the purchases went through.
In addition to those killed, another 20 people were injured in the shooting. Eight survivors remained in hospital at two San Antonio-area hospitals, their condition ranging from good to critical.
Brooke Army Medical Center reported five adults, listed in good to critical condition. University Health System had two children and one adult still in care, with their conditions ranging from fair to serious.
Further details on those in hospital were not released.
